I can produce music with varying level of details depending on the day.

Sometimes it's limited to humming, sometimes it's a full orchestra. Right now I'm listening to Bohemian Rhapsody in my head with the voice of Freddy Mercury and all instruments when I didn't hear the song in probably a year.

I used to remember nothing of my dreams but after a couple weeks of writing them down every morning, even if just a sentence to say I don't recall anything, they became much more vivid and I could recall pages of details.

I have very very vivid dreams today, in complete opposition to the blackness of trying to visualize while awake.

It's quite obvious there are many reasons one could develop aphantasia from the information we can gather here and there, but in my very own case it really makes sense.

I do get imagery from time to time, uncontrollable, very dim and vague, disappearing in an instant, so I'd say the part in charge of producing these images is here, it's just as if it was in "off" position 99% of the time.

I recall being a kid that everyone around from family to teachers kept saying I had a very productive imagination and I do recall that I was always playing in my imagination. I could sit and pretend to have super-powers and stuff and play it all in my mind.

I can't recall when I lost it, but I did live in a traumatic environment for many years and today I can't recall ever playing anything in my mind from after this time.

Basically, to experience hypnotic effects you need to be in the proper state of mind and visualization is very efficient at helping you get there.

When you experience aphantasia, you're involuntarily resistant to hypnosis that uses visualization as a trigger to induce transe. It doesn't mean that it won't work, but this will require the hypnotist to use wording that will evoke concepts you're familiar with rather than images that you should see. For example, saying you have very light balloons tied to your hands and asking you to try and feel how your hands get lighter might work because you do not need to see the balloons to understand the concept of lighter hands. However asking you to picture the balloons, how they look and how big they can grow will have no effect because you can't give life to these images.

Fortunately, hypnosis is not really about visualization and someone with a proper training can work around this resistance. Basically, with a small pre-talk to put you in a mood and careful wording, you can easily experience ideomotor movements, say your hands being dragged one to another, without visualization. Once this is obtained, the technique called "signaling" can be used to negotiate an effect with your unconscious without you understanding the mechanisms at play.

Here's how it happened with me:

During a training, people were unable to obtain from me a catalepsy (two feet stuck in ground) because the visualization techniques they used on each other (think of your feet stuck in cement) had no effect on me.

The trainer used signaling and asked my unconscious if it was ok with trying to find a solution that would make the catalepsy work. It took a few minutes and I could feel an internal struggle which eventually led to a "yes" and my feet were stuck.

The only difference between the others and myself is that they can explain what let them experience this, whereas I have no idea why it worked, it just did.

Another very good book by same author and editor is "Designing BSD rootkits" which explains a few methods to ... design a BSD root kit.

Rootkit put aside, the book goes through various subsystems and it gives an easy to grasp overview of how some things are done in the kernel, ranging from memory allocation to how to replace a system call with your own, etc...

I've read the first edition a few years ago and I'm currently reading the second edition, I find them very practical.

It will not convert you into a kernel hacker magically, the theory that is in the book is actually necessary to grasp the practical parts which are also part of the book. The chapter about UVM, to name just one, has descriptions about the various structures that come into play, where they are used, how they interact, and this is as practical as you're going to get from a book.

I could say the same about the chapter on jails or networking, this book is part of the all-times best CS books I've read.

PS: This is a honest point-of-view, I'm an OpenBSD developer, I don't really use FreeBSD beyond porting purposes.

When the daemon has to deliver a message, it has to fork a MDA that will run with the privileges of the recipient user. If your recipient is root, then this means that the MDA will have absolute privileges.

For any other method than mbox and maildir, OpenSMTPD will simply refuse to run a MDA as root and will require you to create an alias to an unprivileged account if you want to receive mail for your root user.

Yes, clearly libtls should be sufficient for our use and will guarantee that the security is handled by this simple interface rather than having smart code in the daemon trying to make sense out of the ugly SSL interfaces.

As the person who wrote the TLS code in OpenSMTPD, and who usually starts cursing as soon as modifications need to be done in that area, I'm looking forward to actually kill that code and implement the new interface :-)

Yup, however I want to point out that it's not just because LibreSSL is part of OpenBSD that this switch is done, there are actually several technical reasons... and I'm not even counting code quality as part of them though it could justify this switch by itself ;-)

I don't have the syndrome and I never tried to OOB but I did experience exploding head a few months ago.

I was dreaming and all of a sudden a loud high buzz caused me to wake up. The buzz wouldn't go away and was very painful, it ended when I stood up and resumed when I laid back. It eventually went away ... and triggered again later the same night forcing me to just give up on sleeping.

It lasted only a few minutes but they were very painful and it made me anxious of going to sleep the next couple days.

The advisory they published recommended that people upgrade their openssl library ... no mention to the fact that keys should be considered as compromised and that the impact of the bug goes beyond a package update.